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CH1012
ORTHO-PARA
DIRECTING
The reason for the ortho-para direction is the
presence of more resonance structures, eg.
where +ve
is found on
the oxygen.
An example of
an ortho-para directing rxn.
Z = OCH3 - this
directs NO2 to come
in ortho-para.
directs NO2 to come
in ortho-para.
• This means
there is a
lower barrier
to forming
this intermed
& so this is
the product
formed.
there is a
lower barrier
to forming
this intermed
& so this is
the product
formed.
